Chris is at the florist and wants to buy flowers. Arrangements of daisies are $4.25 and the arrangements of roses are $6.50. He wants to spend less than $39 and wants to buy at least 4 arrangements.

Let's define the variables:

D = arrangements of daisies that he buys

R = arrangements of roses that he buys.

Each arrangement of daisies costs $4.25, then for D of them, the total cost is:

D*$4.25

And for the roses, the cost of each one is $6.50, then the cost for R of them is:

R*$6.50

We know that he wants to spend less than $39, then we have the inequality:

D*$4.25 + R*$6.50 < $39

And we also know that he wants to buy at least, 4 arrangements, then:

D + R ≥ 4

Now we have a system of inequalities:

D + R ≥ 4

D*$4.25 + R*$6.50 < $39

This has quite a few solutions, for example, he could buy 3 arrangements of daisies and 2 of roses, the total cost would be:

3*$4.25 + 2*$6.50 = $25.75, which is less than $39, and he is buying 5 arrangements, more than 4 as he wanted.

And there are a lot of other possible options.

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